Drum-type debarking apparatus including log deflector means

ABSTRACT

Drum-type debarking apparatus comprising a log deflector within the drum, wherein the log deflector is provided with an upwardly facing log deflecting face angled between 35* to 45* from the vertical; and the lower end of such log deflecting face is operatively associated with the drum for supplying logs thereto (and hence to the drum carried debarking tools) without substantial velocity of the supplied logs in the circumferential direction of the drum rotation. Above such log deflecting face, the deflector may include a second deflecting face which is angled thereto; and provision is made for introducing liquid and/or steam into the drum.

Dec. 2, 1975 DRUM-TYPE DEBARKING APPARATUS INCLUDING LOG DEFLECTOR MEANS OTHER PUBLICATIONS The Institute of Paper Chemistry, Bibliographic Series,

No.190, Supplement 11, Entry 82, 1972.

Primary ExaminerAl Lawrence Smith Assistant ExaminerGary L. Smith [57] ABSTRACT Drum-type debarking apparatus comprising a log deflector within the drum, wherein the log deflector is provided with an upwardly facing log deflecting face angled between 35 to 45 from the vertical; and the lower end of such log deflecting face is operatively associated with the drum for supplying logs thereto (and hence to the drum carried debarking tools) without substantial velocity of the supplied logs in the circumferential direction of the drum rotation. Above such log deflecting face, the deflector may include a second deflecting face which is angled thereto; and provision is made for introducing liquid and/or steam into the drum.

29 Claims, 6 Drawing Figures US. Patent Dec. 2, 1975 Shet 1 of2 3,923,087

us. Patent D602, 1975 sheet zof z 3,923,087

DRUM-TYPE DEBARKING APPARATUS INCLUDING LOG DEFLECTOR MEANS Embodiments of debarking apparatus of this general type are, for example, described in US. Pat. Nos. 3,807,469 and 3,807,470, both issued Apr. 30, 1974. An object of the present invention is to provide new and improved debarking apparatus of the type set forth wherein the deflector means is particularly constructed and arranged for control of the velocity of the logs.

Another object of the invention is toprovide new and improved debarking apparatus of the type set forth wherein the deflector means is particularly constructed and arranged to prevent incremental increase of the velocity of the logs. Another object is to provide new and ,improved debarking apparatus of the type set forth wherein the de-' flector means is particularly constructed and arranged to supply the logs to the drum without substantial log velocity in the circumferential direction of the drum driven rotation.

Another object is to provide new and improved debarking apparatus of the type set forth wherein the deflector means is particularly constructed and arranged to prevent log stagnation.

Another object is to provide new and improved debarking apparatus of the type set forth wherein the deflector means is particularly constructed and arranged to prevent log stratification by size.

Another object is to provide new and improved debarking apparatus of the type set forth wherein the deflector means is particularly constructed and arranged to cause the logs to be presented to drum carried debarking tool means whereby the debarking action of the tool means on the logs is maximized.

Other objects and advantages will be apparent from the following description taken in connection with the accompanying drawings wherein, as will be understood, the preferred embodiments of the invention have been given by way of illustration only.

In accordance with the invention, debarking apparatus may comprise drum means adapted to be rotatably driven in a predetermined circumferential direction, and log deflector means within the drum means for controlling log movement therein during. such rotation of the drum means, the drum means being rotatable relative to the log deflector means, the log deflector means including log deflecting face means angled between about 35 to about 45 from the'vertical for downwardly directing logs towards its lower end, and such lower end of the log deflecting face means being operatively associated with the drum means for supplying logs to the drum means without substantial velocity of the logs in said predetermined circumferential direction of the rotation of the drum means.

Referring to the drawings:

FIG. 1 is an elevational side view of one embodiment of debarking apparatus constructed in accordance with the invention;

FIG. 2'is a substantially enlargedyeleva'tional sectional view of such embodiment taken on Line 2-2 in FIG. 1, looking in the direction of the arrows;

FIG. 3 is a fragmentary elevational sectional view of a second embodiment of debarking apparatus con-' structed in accordance with the invention; and

FIGS. 4 through 6are fragmentary elevational sectional views of three other embodiments constructed in accordance with the invention. Referring more particularly to the drawings wherein similar reference characters designate corresponding parts throughout the several views, FIGS. 1 and 2 illustrate a debarking apparatus comprising an annular,

elongated drum or drum means,- designated generally as 10, having an open inlet end 12 adapted to receive unbarked logs 14 from a feed conveyor 16 and an open discharge end 18 adapted to discharge the debarked logs 20'to a discharge chute'22. The drum 10 may include the usual bark discharge openings 24 and, although shown as being substantially horizontal, may be alternatively angled downwardly from its inlet end 12 towards its discharge end 18 to facilitate the passage of logs longitudinally therethrough. The drum 10 includes a pair of annular circumferential tires 26 at spaced locations along its length and is rotatably mounted by pairs of rotatable trunion rollers 28 rotatably engaging each of the tires 26, it being understood that only one of each pair of the rollers 28 has been shown in FIG. 1. The drum 10 rigidly carries an annular, circumferen tial, toothed gear 30 intermeshing with a driving pinion 32'a'nd is rotatably driven in the clockwise direction, as viewed in FIG. 2, by aconventional, variable speed, driving motor 34 which is drivingly connected to the pinion 32 through a conventional speed reducer 36. It will be understood, however, that such illustrated drum mounting and pinion driving arrangements have been shown only for the purposes of illustration; and the drum 10 may be otherwise suitably rotatably mounted and driven.

The drum inner circumference carries debarking tools 38 particularly adapted for applying high unit pressure; localized, hammer-like, impact blows to logs in the drum 10 during the drum driven rotation.- As illustrated, the debarking tools 38 are in the form of relatively small, blunt protrusions arcuately contoured on all working sides to prevent log damage and arranged in annular sets mounted on the drum inner circumference by annular mounting rings 40 affixed to the latter. It will be understood, however, that the tools 38 could alternatively be of other configuration suitable to provide the described impact blows to the logs without log damage and/or otherwise suitably mounted on the drum 10. It will, moreover, be understood that, although the sets of the tools 38 are provided at intervals throughout the entire length of the drum 10, the tools 38 could be alternatively provided for only a portion of the drum length in other embodiments of the debarking apparatus.

An elongated log deflector or anvil 42 longitudinally extends completely through the drum l0 and at itsopposite ends is rigidly supported by ground-mounted supporting frames 44,46 located adjacent the drum inlet and discharge ends 12, 18, respectively. The log deflector 42 is of the hereinafter described crosssection shown in FIG. 2 throughout the length of the drum l0-and mounted on the supporting frames 44,46 to be retained in fixed positionthroughout the driven rotation of the drum 10 around it. The log deflector 42 is disposed completely within the downturning side or half of the drum l0 that is, as viewed in FIG. 2

wherein the drum 10 is rotatably driven in the clockwise direction indicated by the arrow, in the right-hand half of the drum interior and below the portion of the upper side of the drum l travelling downwardly during the drum driven rotation. The log deflector 42 includes upper and lower ends 48,50, respectively, and adjacent its lower end 50 is relatively arranged with the drum for downwardly supplying logs to the inner circumference of the drum 10 (and, hence, to the tools 38 mounted thereon) without substantial velocity of the logs in the circumferential or rotary direction of the drum driven rotation.

More particularly, as shown in FIG. 2, the log deflector 42 includes a log deflecting face or surface 52 of length 54 which faces generally upwardly and inwardly towards the center 56 of the drum 10. The log deflecting face 52 throughout its length 54 is at an angle of between about 35 to about 45 from the vertical and serves to downwardly direct the logs to its lower end 58 where the logs are caused to drop at least generally vertically downwardly to the therebelow portion of the drum 10 and, hence, to the debarking tools 38. Angling of the deflecting face 52 within the described about 35 to about 45 range is an important feature of the invention in that it causes the face' 52 to be sufficiently inclined to downwardly direct the logs without log stagnation while also causing the incline of the face 52 to be sufficiently limited whereby excessive downward velocity of the logs is precluded to assist in preventing incremental log velocity build-up within the drum 10. The lower end 58 of the face 52 is spaced inwardly of the drum 10 above the therebelow debarking tools 38 a vertical distance 60 which is between about seven and one-half percent to about twenty percent of the drum inner diameter and one-half of the diameter of the largest diameter log expected to be debarked by the apparatus. The spacing of the lower end 58 such described distance 60 above the debarking tools 38 causes the logs passing downwardly from the lower end 58 to the drum l0 and its carried tools 38 to be supplied to the drum l0 and tools 38 at least generally vertically and without substantial velocity in the circumferential direction of the drum driven rotation. Hence, the relative circumferential velocity between such supplied logs and the tools 38 to which they are supplied, is resultantly maximized to enhance the debarking action of the tools 38 on the logs. Also, the logs are resultantly prevented from receiving incremental increases in velocity in the direction of the drum driven rotation as they are each thusly supplied, thereby preventing rotation of the entire log mass with resultant log stratification by size that is, maintenance of generally stagnant larger logs in the center of the log mass in the drum 10 and circulation of smaller logs around such larger logs that might otherwise occur. Uniform debarking of the logs is thereby greatly facilitated while wood loss on the smaller logs is substantially minimized.

Above the deflecting face 52 and on the same side as the latter, the log deflector 42 includes a second log deflecting face 62 of length 64 which is angled relative to the face 52 to prevent log stagnation adjacent the upper end' of the log deflector 42 when the drum 10 is heavily loaded with logs. The second deflector face 64 is, as shown in FIG. 2, arcuately contoured to arcuately extend at a steeper angle to the vertical than the face 52 and at its lower end merges into the upper end of the face 52. At its upper end 48, the log deflector 42 at spaced intervals along its length carries comb-like projections 66 extending between adjacent ones of the mounting rings 40 which mount the tools 38 to the drum 10. The comb-like projections 66, as will be understood, serve to prevent smaller diameter logs from passing downwardly into the arcuate space 68 between the drum l0 and the thereadjacent arcuate outer periphery 70 of the log deflector 42. In addition, adjacent the upper end of the log deflector 42 there may be provided a liquid supply header 72 arranged for supplying liquid downwardly onto the second anvil face 52 whereby such liquid passes downwardly therefrom along the anvil face 52 for wetting the faces 52,62 to reduce the friction of the logs thereon. The liquid header 72 is connected in a conventional manner to a source of water or other suitable liquid and, as will be understood, is particularly useful when the logs being debarked include particularly sticky bark or excessively dry bark.

Below the deflecting face 52 and on the same side as the latter, the log deflector 42 includes a lower end face 74 which extends vertically downwardly from the lower end 58 of the deflecting face 52. The lower end face 74 serves to protect a steam header 76 and associated steam discharge pipes 78, opening through the lower end face 74, from damage by logs falling downwardly from the lower end 58 of the deflecting face 52, the vertical disposition of the lower end face 74 serving, of course, to insure that the latter does not interfere with the beforedescribed supply of logs from the lower end 58 to the drum l0 and tools 38. The steam header 76 is, in a conventional manner, connected to a suitable source of steam and supplies the steam through the pipes 78 adjacent and below the lower end 58 of the deflecting face 52, whereby such supplied steam serves to facilitate the debarking.

Throughout the operation of the debarking apparatus, the drum 10 is continuously rotatably driven in the direction schematically depicted by the arrows in FIG. 2 by the motor 34; and unbarked logs 14 are longitudinally fed by the log feed conveyor'16 into the drum inlet end 12 while debarked logs 20 are discharged by the drum discharge end 18 onto the discharge chute 22. Within the drum 10, there is normally maintained a log mass having an upper free surface at an angle of about 45 to the horizontal; and such free surface of the log mass is normally maintained at a height within the range schematically depicted by the arrow 80 shown in FIG. 2. The deflector face 52 directs the logs downwardly towards its lower end 58 at a velocity controlled by its angling relative to the vertical; and at such lower end 58 the logs are discharged downwardly to the therebelow portion of the drum 10 and tools 38. The logs are thus supplied to the drum l0 and tools in a direction wherein substantially all of the velocity of the supplied logs is in the direction other than the circumferential direction of the drum driven rotation. Throughout such operation, the deflector face 62 prevents log stagnation adjacent the upper end of the log deflector 42; and the comb-like projections 66 prevent loss from passing between the drum 10 and the arcuate outer periphery 70 of the deflector 42. The recirculatory pattern of the logs is generally as schematically depicted by the broken arrows shown in FIG. 2, the rotation of the drum 10 serving the cause the logs to be carried upwardly to the top of the free surface 80 wheretowards from that beforedescribed only in that the second log" deflector face 62a is arcuately contoured wi h a much smaller radius. I I

FIG. 4, wherein parts corresponding to those 'of FIGS. 1 and 2 are designated by the corresponding reference character followed by the suffix b, illustrates an alternative embodiment which differs from'thatof FIG. 1 only in that the second log deflectorface 62b is verti-- cal and the lower end face 74b is not vertical, but rather arcuately contoured to extend in the opposite direction from the drum driven rotation. i

FIG. 5, wherein parts corresponding FIGS. 1 and 2 are designated by the corresponding reference character followed by the suffix illustrates another alternative form of the invention-which differs from that of FIG. 4 only in that the log deflector 42c includes no lower end face and the deflecting face 62c is slightly angled from the vertical.

FIG. 6, wherein parts correspondingto those of FIGS. 1 and 2 are designated by the corresponding ref erence character followed by the suffix d, illustrates yet another alternative embodiment v of vthe invention wherein the second deflector face is eliminated and the deflector face 52d extends the full length of thedeflector 42d with the liquid supply header 72d arranged to directly supply the liquid onto the deflector face 52d.

The operation of the embodiments of FIG. 3 through 6 is believed to be apparent fromv the preceding description of the operation of the embodiment of FIGS 1 and 2.

From the preceding description it will be seen that the invention provides new and improved means for attaining all of the beforedescribed objects and advantages. It will be understood, however, that, although only a few embodiments of the invention have been illustrated and hereinbefore specifically described, the invention is not limited merely to these few embodiments but rather contemplates other embodiments and variations within the scope of the following claims. It will be further understood that, although the beforedescribed debarking apparatus includes a drum means comprising only a single drum 10, debarking apparatus constructed in accordance with the invention could alternatively include a drum means comprised of a plurality of end-to-end drums. Moreover, in this latter event separate log deflectors could be provided for each of the drums or, if desired, a single log deflector could be arranged to extend through all of the drums.

Having thus described my invention, I claim:

1. Debarking apparatus comprising drum means adapted to be rotatably driven in a predetermined rotary direction, log deflector means within said drum means for controlling log movement therein during such rotation of said drum means, and means supporting said log deflector means such that said drum means is rotatable relative to said log deflector means, said log deflector means including log deflecting face means disposed generally upwardly facing and angled between about 35 to about 45 from the vertical for downwardly directing logs towards its lower end, and such lower end of said log deflecting face means being operto' those of atively associated'with said drum means for supplying logs to said'drum means without substantial velocity of the logs in said predetermined rotarydirection of the rotation of said druni'me'ans.

2?.Debarking apparatus according to claim 1; further" comprising means at the upper'end of said log deflector means for'preventing log movernent around said log deflec'tor means between thelatter and said drum means. 3. Debarking apparatus according to claim 1,

wherein such lower endof said log deflecting face means is operatively associated with said'drurn means' for causing the logs to be at least generally vertically suppliedto said drum means. i

4. Debarking apparatus according to claim 1, wherein said log deflecting face means is disposed within the downturning side of said drum means;

5. Debarking apparatus according to claim 1, wherein said log deflector means includes second log deflecting face means above said first mentioned log deflecting face means, and said second'log deflecting face means is angled relative to said first mentioned log deflecting face, means for downwardly directing logs towards said first mentioned log deflecting face means and preventing log stagnation above the latter.

6. Debarking apparatus according to claim 5,

I wherein said second logdeflecting face means is angled from the vertical at a smaller angle than said first menwherein said second log deflecting face means is arcuately contoured.

9. Debarking apparatus according to claim 5, wherein both of said'log deflecting face means are in the downturning side of said drum means.

, 10. Debarking apparatus according to claim 1, further comprising liquid supply means for supplying liquid to said log deflector means whereby such liquid passes downwardly over said log deflecting face means.

11. Debarking apparatus according to claim 10, wherein said liquid supply means is arranged to supply the liquid adjacent the upper end of said log deflector means.

12. Debarking apparatus according to claim 1, further comprising steam supply means for supplying steam into said drum means.

13. Debarking apparatus according to claim 12, wherein said steam supply means is arranged to supply the steam adjacent the lower end of said log deflector means.

14. Debarking apparatus according to claim 1, further comprising a plurality of debarking tool means carried by said drum means within said drum means, and wherein the lower end of said log deflecting face means is spaced above therebelow ones of said debarking tool means a vertical distance between about seven and one-half percent and about twenty percent of the inner diameter of said drum means.

15. Debarking apparatus comprising drum means adapted to be rotatably driven in a predetermined circumferential direction, log deflector means within said drum means for controlling log movement therein during such rotation of said drum means, and means supporting said log deflector means such that said drum means is rotatable relative to said log deflector means,

said log deflector means including log deflecting face means angled between about 35 to about 45 from the vertical for downwardly directing logs towards its lower end, said log deflecting face means being generally upwardly facing and within the downturning side of said drum means, and the lower end of said log deflecting face means being operatively associated with said drum means for downwardly supplying logs to said drum means whereby at least substantially all of the velocity of such supplied logs is in a direction other than said predetermined circumferential direction of the rotation of said drum means.

16. Debarking apparatus according to claim 15, wherein the lower end of said log deflecting face means is operatively associated with said drum means to cause logs to be supplied to said drum means at least generally vertically.

17. Debarking apparatus according to claim 15, wherein the entire said log deflector means is in the downturning side of said drum means.

18. Debarking apparatus according to claim 15, further comprising a plurality of debarking tool means carried by said drum means within said drum means, and wherein the lower end of said log deflecting face means is spaced above therebelow ones of said debarking tool means a vertical distance between about 7% percent and about 20 percent of the inner diameter of said drum means.

19. Debarking apparatus according to claim 18, wherein said debarking tool means comprises means for applying high energy, localized impact blows to the logs.

20. Debarking apparatus according to claim 18, wherein said log deflector means includes second log deflecting face means above said first mentioned log deflecting face means and on the same side as the latter, and said second log deflecting face means is angled relative to said first mentioned log deflecting face means to downwardly direct logs towards said first mentioned log deflecting face means and prevent log stagnation above the latter.

21. Debarking apparatus according to claim 20, wherein said second log deflecting face means is angled from the vertical at a smaller angle than said first mentioned log deflecting face means.

22. Debarking apparatus according to claim 20, wherein said second log deflecting face means is at least generally vertical.

23. Debarking apparatus according to claim 20, wherein said second log deflecting face means is arcuately contoured.

24. Debarking apparatus according to claim 20, wherein both of said log deflecting face means are in the downturning side of said drum means.

25. Debarking apparatus according to claim 18, further comprising liquid supply means for supplying liquid to said log deflector means whereby such liquid passes downwardly on said log deflecting face means.

26. Debarking apparatus according to claim 25, wherein said liquid supply means is arranged to supply the liquid adjacent the upper end of said log deflector means.

27. Debarking apparatus according to claim 18, further comprising steam supply means for supplying steam into said drum means.

28. Debarking apparatus according to claim 27, wherein said steam supply means is arranged to supply the steam adjacent the lower end of said log deflector means.

29. Debarking apparatus according to claim 18, further comprising means at the upper end of said log deflector means for preventing log movement around said log deflector means between the latter and said drum means. 

1. Debarking apparatus comprising drum means adapted to be rotatably driven in a predetermined rotary direction, log deflector means within said drum means for controlling log movement therein during such rotation of said drum means, and means supporting said log deflector means such that said drum means is rotatable relative to said log deflector means, said log deflector means including log deflecting face means disposed generally upwardly facing and angled between about 35* to about 45* from the vertical for downwardly directing logs towards its lower end, and such lower end of said log deflecting face means being operatively associated with said drum means for supplying logs to said drum means without substantial velocity of the logs in said predetermined rotary direction of the rotation of said drum means.
 2. Debarking apparatus according to claim 1, further comprising means at the upper end of said log deflector means for preventing log movement around said log deflector means between the latter and said drum means.
 3. Debarking apparatus according to claim 1, wherein such lower end of said log deflecting face means is operatively associated with said drum means for causing the logs to be at least generally vertically supplied to said drum means.
 4. Debarking apparatus according to claim 1, wherein said log deflecting face means is disposed within the downturning side of said drum means.
 5. Debarking apparatus according to claim 1, wherein said log deflector means includes second log deflecting face means above said first mentioned log deflecting face means, and said second log deflecting face means is angled relative to said first mentioned log deflecting face means for downwardly directing logs towards said first mentioned log deflecting face means and preventing log stagnation above the latter.
 6. Debarking apparatus according to claim 5, wherein said second log deflecting face means is angled from the vertical at a smaller angle than said firSt mentioned log deflecting face means.
 7. Debarking apparatus according to claim 5, wherein said second log deflecting face means is at least generally vertical.
 8. Debarking apparatus according to claim 5, wherein said second log deflecting face means is arcuately contoured.
 9. Debarking apparatus according to claim 5, wherein both of said log deflecting face means are in the downturning side of said drum means.
 10. Debarking apparatus according to claim 1, further comprising liquid supply means for supplying liquid to said log deflector means whereby such liquid passes downwardly over said log deflecting face means.
 11. Debarking apparatus according to claim 10, wherein said liquid supply means is arranged to supply the liquid adjacent the upper end of said log deflector means.
 12. Debarking apparatus according to claim 1, further comprising steam supply means for supplying steam into said drum means.
 13. Debarking apparatus according to claim 12, wherein said steam supply means is arranged to supply the steam adjacent the lower end of said log deflector means.
 14. Debarking apparatus according to claim 1, further comprising a plurality of debarking tool means carried by said drum means within said drum means, and wherein the lower end of said log deflecting face means is spaced above therebelow ones of said debarking tool means a vertical distance between about seven and one-half percent and about twenty percent of the inner diameter of said drum means.
 15. Debarking apparatus comprising drum means adapted to be rotatably driven in a predetermined circumferential direction, log deflector means within said drum means for controlling log movement therein during such rotation of said drum means, and means supporting said log deflector means such that said drum means is rotatable relative to said log deflector means, said log deflector means including log deflecting face means angled between about 35* to about 45* from the vertical for downwardly directing logs towards its lower end, said log deflecting face means being generally upwardly facing and within the downturning side of said drum means, and the lower end of said log deflecting face means being operatively associated with said drum means for downwardly supplying logs to said drum means whereby at least substantially all of the velocity of such supplied logs is in a direction other than said predetermined circumferential direction of the rotation of said drum means.
 16. Debarking apparatus according to claim 15, wherein the lower end of said log deflecting face means is operatively associated with said drum means to cause logs to be supplied to said drum means at least generally vertically.
 17. Debarking apparatus according to claim 15, wherein the entire said log deflector means is in the downturning side of said drum means.
 18. Debarking apparatus according to claim 15, further comprising a plurality of debarking tool means carried by said drum means within said drum means, and wherein the lower end of said log deflecting face means is spaced above therebelow ones of said debarking tool means a vertical distance between about 7 1/2 percent and about 20 percent of the inner diameter of said drum means.
 19. Debarking apparatus according to claim 18, wherein said debarking tool means comprises means for applying high energy, localized impact blows to the logs.
 20. Debarking apparatus according to claim 18, wherein said log deflector means includes second log deflecting face means above said first mentioned log deflecting face means and on the same side as the latter, and said second log deflecting face means is angled relative to said first mentioned log deflecting face means to downwardly direct logs towards said first mentioned log deflecting face means and prevent log stagnation above the latter.
 21. Debarking apparatus according to claim 20, wherein said second log deflecting face means is angled from the vertical at a smaller angle than said first mentioned log deflecting face means.
 22. Debarking apparatus according to claim 20, wherein said second log deflecting face means is at least generally vertical.
 23. Debarking apparatus according to claim 20, wherein said second log deflecting face means is arcuately contoured.
 24. Debarking apparatus according to claim 20, wherein both of said log deflecting face means are in the downturning side of said drum means.
 25. Debarking apparatus according to claim 18, further comprising liquid supply means for supplying liquid to said log deflector means whereby such liquid passes downwardly on said log deflecting face means.
 26. Debarking apparatus according to claim 25, wherein said liquid supply means is arranged to supply the liquid adjacent the upper end of said log deflector means.
 27. Debarking apparatus according to claim 18, further comprising steam supply means for supplying steam into said drum means.
 28. Debarking apparatus according to claim 27, wherein said steam supply means is arranged to supply the steam adjacent the lower end of said log deflector means.
 29. Debarking apparatus according to claim 18, further comprising means at the upper end of said log deflector means for preventing log movement around said log deflector means between the latter and said drum means. 